The present invention refers to a bearing unit for driven or non-driven wheels of vehicles or the like.
Wheels e.g. for motor cars are conventionally supported on rolling bearings arranged on a shaft pivot. As such an assembly it is necessary accurately to machine a number of contact surfaces of the bearings, the shaft pivot or the surrounding housing or hub and to adjust the bearings to a correct preload in situ.
In later years it has been suggested to substitute the conventional supporting method by arranging a bearing unit, which incorporates bearing as well as wheel hub. This unit can be attached directly to a supporting portion of the vehicle and the wheel can be fitted directly to the part of the unit intended for rotation. A plurality of types of such units are presently known, and one of them is described e.g. in British Patent Specification No. 1.519.048.
The unit described in this patent consists of a rotatable inner member 3, a stationary outer member 2 and a two-row angular contact ball bearing 10. The bearing as shown is provided with a double retainer 11, which encloses both rows of balls. The unit is furthermore provided with two seals 12 and 13 of which seal 13 has been given a particular design, whereas the easily accessible seal 12 is of conventional type.
In assembling a bearing unit of this type, it is necessary to use the so called Konrad assembly, which means that the outer and inner rings are given an eccentric position in relation to each other during the introduction of the balls, whereupon the rings are brought to concentric position relative to each other and the retainer is inserted from one side, i.e. from the right hand side as shown in the drawing figure. It is thus necessary that the retainer is of the so called snap-type. It is also necessary that the seal 13 is made of such an elastic material that it will not impede an eccentric dislocation of the outer and inner rings relative to each other during the introduction of the balls. It is easily realized at a glance at the drawings that the seal 13 must be fixed to the outer ring 2 prior to the assembly of the bearing unit.
It has since long been a desideratum to be able to use a conventional seal at this bearing unit also in the space adjacent the inner and outer race rings, and to be able to use a separate retainer for each row of balls. A common seal, as for example the seal 12 is rigid, and it can therefore not be fixed to the outer ring prior to a Konrad-assembly, since it will prevent an eccentric dislocation of the inner and outer rings relative to each other. A further study of the drawings of said specification shows furthermore that it is impossible to introduce a retainer for the left hand row of balls, as there is no space for displacing the retainer to the left prior to the assembly.
This problem has according to the present invention been solved and it has been provided a bearing unit for driven or non-driven wheels of vehicles or the like, which incorporates a radially inner member and a radially outer member have confronting raceways for a plurality of rolling bodies or elements, retainer and seals arranged therebetween, whereby at least the radially inner member is provided with flange-like members for attachment of the unit to the wheel or the vehicle or the like, and which is characterized thereby that the flange-like member, which extends radially outwardly beyond the rolling bodies, is provided with recesses which make possible mounting and inspection of retainer and/or seals from the exterior of the flange-like member.
Further features of the invention are defined in the sub-claims.
By means of the present invention is it possible by aid of a simple tool to push the retainer and the seal, or if a double retainer is used, only the seal, into the bearing from the flange side.
As to the seal it is besides the simplfied assembly also gained that it is possible to use a rigid seal of conventional type, as the seal does not have to be inserted during the Konrad-assembly.